1. Field of the Invention
The present invention relates to a trailing device in trailing art, more especially, to a trailer system for inspecting a vehicle and an inspection system having the same which are widely used in radiation imaging inspection.
2. Description of the Related Art
Trailers are always used in radiation imaging inspection.
The radiation imaging inspection is indispensable for customs, civil airport and railway station. A system used in radiation imaging inspection is normally operated as follows: a radiation source and detector arrays capable of receiving detecting rays penetrating through a vehicle to be inspected are provided in a detecting passage that can shield rays; the vehicle to be inspected is trailed through radiating beams for inspection by a special trailing device. And the system generally comprises subsystems such as an accelerator, a detector, a image acquiring and scanning device, and a running and inspecting device. During inspection, the vehicle to be inspected rapidly passes through the scanning passage, which is essential to the radiation imaging inspection. In prior art, the special trailing device includes a flat car and various trailing bogies or the like.
Chinese Patent No. CN00107480.6 discloses an automatic flatcar for a fixed container inspection system. During inspection, the vehicle to be inspected is driven onto the automatic flatcar. Longitudinal and horizontal travel mechanisms are installed at the bottom of the automatic flatcar, and the travel mechanisms circulate or reciprocate on rectangular rails so that the vehicle to be inspected is smoothly transmitted through the scanning passage. However, the automatic flatcar has following disadvantages: it has to bear total weight of the vehicle to be inspected including the cargo. In addition, the automatic flatcar has a large trailer body with complex structure, which leads to high cost and maintenance fees.
On the other hand, Chinese Patent No. CN200310100184.0discloses a trailer for a radiation imaging trailer system. The trailer comprises a trailer frame, vehicle wheels and turning member. During working, the trailer only drags front wheels of the vehicle to be inspected, and the rear wheels 203 follow accordingly. There is a climbing slope and a declining slope at both ends of the trailer frame, and a turning member on the trailer frame. During inspection, the turning plate abuts against the front wheels of the vehicle to be inspected, and the vehicle to be inspected is dragged through the scanning passage by the trailer. According to the solution disclosed therein, when the vehicle to be inspected runs away from the trailer, since, on one hand, the turning plate is opened, it may scrape the chassis, oil tank and other components, at the bottom of the vehicle to be inspected. On the other hand, since the climbing and declining slopes are provided on the trailer, the length of the trailer is not enough for structural restraints, for the vehicle to be inspected having longer wheelbase, the front wheels has left the trailers where as the rear wheels 203 thereof has not left the trailers yet during unloading of the vehicle to be inspected, which may cause the vehicle to straddle over the trailer. In addition, this may also leads to the chassis to be inspected and the bottom attachments being scraped by the trailer easily, thus the vehicle to be inspected is damaged, which may further influence the normal working of the radiation imaging system. Therefore, the invention thereof reduces the reliability of the system when used for the radiation imaging system. Especially, the invention is not adapted for trailing heavily loaded vehicle with low chassis and long wheelbase.